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The heavy metals namely Fe, As, Cu, Cd, and Pb were investigated in two marine fishes silver pomfret (Pampus argentus) and torpedo scad (Megalaspis cordyla), and three seafoods sibogae squid (Loligo sibogae), Indian white prawn (Fenneropenaeus indicus), and mud crab (Scylla serrata) by using inductively coupled plasma spectrophotometer (ICP-MS) from two renowned fish harvesting coastal area of Malaysia named as Kedah and Selangor. Among the target heavy metals, highest mean concentration of As and Fe were found in Scylla serrata (72.14±7.77 μg/g) in Kedah and Megalaspis cordyla (149.40±2.15 μg/g) in Selangor. Pearson's correlation results showed As-Fe-Cd-Cu originated from the same source. Maximum estimated daily intake (EDI) values of Scylla serrata were found 175.25 μg/g/day and 100.81 μg/g/day for child in both Kedah and Selangor areas respectively. Hazard quotient (HQ) and hazard index (HI) results revealed that local consumers of Kedah and Selangor will face high chronic risk if they consume Scylla serrata, Fenneropenaeus indicus, and Megalaspis cordyla on regular basis in their diet. Carcinogenic risk results suggested that all the studied species pose very high risk of cancer occurrences to the consumers in both areas. Therefore, it could be recommended that consumers should be aware when they are consuming these marine species since they can pose serious health risk associated with prolonged consumption.

This study examines the performance of a parabolic greenhouse-type solar dryer used for drying of cayenne pepper (Capsicum annuum) in Nan (northern Thailand). The dryer has a base area of 6.0 m × 8.2 m and a height of 3.25 m with the loading capacity of 100–200 kg for fruit or vegetables. It has a parabolic roof structure covered with polycarbonate sheets and is placed on a concrete floor. It is ventilated by three DC fans powered by a 50-Watt solar cell module. The produce is placed on trays with wire mesh base and located on steel supports. Among the advantages of this type of dryer is that the product is protected from rain, dust and insects. The pepper samples consisted of whole pods or cut pods. The drying experiments were carried out in the solar dryer and in an electrical (convective) tray dryer. The study was focusing on drying kinetics and on the effects of the drying treatments on one of the main quality attributes namely the capsaicin content in the dried products.

The proximate, minerals, amino acid and fatty acid composition of wild, pond-, gher- and cage-cultured tilapia in Bangladesh were evaluated and varied significantly (p < 0.05). The major component of the tilapia was moisture (79.12%–81.36%), followed by protein (14.93%–16.03%), lipid (0.59%–2.35%), carbohydrate (1.23%–1.51%), fibre (0.47%–0.88%), ash (0.31%–0.53%); the energy value was between 97.62 and 126.73 kcal/100 g. Macro-nutrients and micro-nutrients were detected in following order: K > Na > Mg > Ca and Fe > Mn, respectively in all the tilapia and the ratio of Na/K was

The heavy metals namely Fe, As, Cu, Cd, and Pb were investigated in two marine fishes silver pomfret (Pampus argentus) and torpedo scad (Megalaspis cordyla), and three seafoods sibogae squid (Loligo sibogae), Indian white prawn (Fenneropenaeus indicus), and mud crab (Scylla serrata) by using inductively coupled plasma spectrophotometer (ICP-MS) from two renowned fish harvesting coastal area of Malaysia named as Kedah and Selangor. Among the target heavy metals, highest mean concentration of As and Fe were found in Scylla serrata (72.14±7.77 μg/g) in Kedah and Megalaspis cordyla (149.40±2.15 μg/g) in Selangor. Pearson's correlation results showed As-Fe-Cd-Cu originated from the same source. Maximum estimated daily intake (EDI) values of Scylla serrata were found 175.25 μg/g/day and 100.81 μg/g/day for child in both Kedah and Selangor areas respectively. Hazard quotient (HQ) and hazard index (HI) results revealed that local consumers of Kedah and Selangor will face high chronic risk if they consume Scylla serrata, Fenneropenaeus indicus, and Megalaspis cordyla on regular basis in their diet. Carcinogenic risk results suggested that all the studied species pose very high risk of cancer occurrences to the consumers in both areas. Therefore, it could be recommended that consumers should be aware when they are consuming these marine species since they can pose serious health risk associated with prolonged consumption.

A gas chromatographic method was developed for the quantitative determination of the monosaccharides of the soluble, insoluble fractions and the total non-starch polysaccharides (NSPs) content in foods with fat contents of less than 5%. Sample preparation involved enzymatic removal of starch and acid hydrolysis of the NSP to their constituent sugars. The alditol acetate derivatives were analysed on a wide bore capillary column with detection by flame ionization. The method was accurate, with recovery of spiked samples between 93.6% and 102.7% for intra-day analysis and between 93.2% and 104.7% for inter-day analysis. Repeatability was excellent; RSD values from 0.1 to 4.4% and 0.2 to 5.7% were observed from intra-day analysis and inter-day analysis, respectively. The peaks for all neutral sugars were sharp and separation was at baseline resolution with no interfering or co-eluting peaks.

This chapter presents some selected types of bioactive compounds from these sources, the way of incorporating them in foods and examples of testing their effects on human health. It deals with the techniques used to study the potential beneficial effects of bioactive phytochemicals for human health. Food is an essential factor for the survival of humans. Among foods that are characterised as functional foods, honey and other products originating from the beehives take a prominent place. Honey, propolis and royal jelly may be used as functional foods because they have high antioxidant potential. The recovery of anthocyanin after extraction depends primarily on the types and concentration of solvents, time, temperature and solvent to solid ratio. Plants have long been used as health foods and sources of medicinal properties. The anthocyanins in a product may present in much lower concentrations than expected because the anthocyanin itself is sensitive to various processing conditions.

This research aimed to develop a suitable coating material for encapsulating a plant bioactive compound via spray drying. A suitable process for modifying the rheological property of konjac glucomannan (KGM) solution by enzymatic treatment was developed. A plant bioactive compound, andrographolide, was selected to use as core material. Mannanase (1500 units of enzyme) was used in the treatment of KGM solution. The concentration of KGM solution was varied from 9 to 18% (w/w). It was found that 12% (w/w) was the optimum KGM concentration that could be hydrolyzed to a viscosity of

Turmeric (Curcuma longa), belongs to Zingiberaceae family. The rhizomes contain bioactive compounds of the curcuminoids group (natural phenols). They are used in food and pharmaceutical industry. The aim of this research was to acquire dried turmeric with high total curcumin content. In this study, optimum turmeric drying conditions and new extraction techniques were explored. Fresh turmeric samples were subjected to constant vs changing drying air temperatures and pre-treatment (blanching). Changing drying air temperature and use of non-blanched turmeric slices resulted in the highest concentration of curcumin. Ultrasonic extraction instead of soxhlet extraction improved the extraction efficiency and decreased extraction time. Keywords: Turmeric, Curcumin; Drying; Blanching; Extraction

Brown kernels or internal discolouration (IDC) in various varieties of Macadamia nuts ( Macadamia integrifolia and Macadamia tetraphylla ) occurred through three different pathways: (i) an enzymatic browning reaction, (ii) Maillard reaction and (iii) infection by microorganisms. The phenolic compounds and polyphenol oxidase (PPO) activities of macadamias were analysed. Brown sections of the same kernel had higher levels of bound phenolics compared to the white sections, indicating the participation of phenolic compounds in the formation of brown kernel. The Maillard reaction was studied by determining the sugar amount using HPLC. The reducing sugars during drying reacted with kernel proteins causing the formation of brown pigments. Among the various varieties studied, ‘Daddow’ variety showed the least degree of hydrolysis. When kernel was infected with Penicillium aurantiogriseum , the kernel turns brown. The internal discoloration in macadamias is the first report that has been explored in our study. The findings of this study have potential to improve the existing postharvest techniques used in the Macadamia processing industry.

Summary Polyphenolic-rich fraction obtained from locally produced dry ginger powder in Brahmaputra valley, India, and commercially available dry ginger (Zingiber officinale) rhizome powder consisted of [6]-gingerol (41.9%), [6]-shogaol (24.3%), 1-dehydro-6-gingerdione (8.6%), [8]-gingerol (7.2%), [10]-gingerol (5.1%), [6]-paradol (5.9%) and [4]-gingerol (3.6%). Traces of methyl-[6]-gingerol and methyl-[8]-gingerol (both at 1.8%) were also detected. The fraction exhibited high antioxidant capacity [total phenolics (TP), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity (CAA assay)], effectively inhibited isolated digestive enzymes (α-glucosidase, pancreatic lipase and angiotensin converting enzyme) and inhibited the proliferation of colon (HT29; IC50 of 1.06 ± 0.02 mg mL−1) and gastric (AGS IC50 of 1.29 ± 0.03 mg mL−1) adenocarcinoma cells, without affecting the proliferation of their nontransformed counterparts (IC50 > 2.0 mg mL−1). This case study demonstrates that locally produced and commercially available dry ginger powder from Brahmaputra valley, India, retains numerous food components that may enhance human health.

International audience; The effects of konjac glucomannan (KGM) on the gelatinization, retrogradation and complexation properties of potato and broad bean starches were investigated by differential scanning calorimetry and X ray diffraction. It was established that the addition of 1% KGM in starch suspensions causes a slight decrease in the amount of available water in the system. However, this seems sufficient to disrupt the gelatinization and the retrogradation of potato and broad bean starches. In addition, the ability of amylose to interact with carvacrol is strongly affected by the presence of KGM. A rheology study showed on one hand that addition of KGM to starch decreased the gel character of the system, irrespective of the presence of carvacrol. However, carvacrol induced a strong increase of the storage modulus of starch gel for the same KGM content.

In this study, new method was investigated using solid phase microextraction (SPME) for detection of insect infestation in stored wheat. The results show that volatile pheromones isolated from a number of common stored grain insects, can be used to indicate infestation. The amounts of pheromone released varied between species. Rhyzopertha dominica (F.) was the highest volatile pheromone producer among the species investigated, then it was followed by Tribolium castaneum (Herbst), Cryptolestes ferrugineus (Stephens) and Cryptolestes pusillus (Schonherr), respectively. This resulted in different sensitivity when SPME was used for detection. A single specimen of T. castaneum and R. dominica could be successfully detected in 1 kg of wheat, whereas more number of C. ferrugineus and C. pusillus beetles were required for detection in the same quantity of grain. Extraction period and temperature affected the sensitivity of the SPME method. Longer exposure time and higher temperature allowed more analytes to be collected. Consequently, extraction for 4 h at 50 °C appeared to be the optimum condition for extracting pheromones produced by the beetles covered by this study. The method was further adjusted to be more practical and this resulted in changing the sensitivity. Detection of a single R. dominica could still be successfully achieved, even though the time and the temperature were reduced, whereas for the remaining species, the minimum number of insects required had to be increased by about 40–60% in order to detect volatile pheromone in headspace. In conclusion, the SPME technique in detection of infestation is still required further development to be applied to the grain industry. Dynamic headspace may help improve the sensitivity of technique.

Davidson's plum (DP; Davidsonia pruriens, F. Muell, Cunoniaceae) and quandong (QD; Santalum acuminatum, A.D.C., Santalaceae) are two leading commercially grown native Australian fruits used in a variety of food products such as jam, chutney, sauces, wine or herbal teas. Within this study their inhibitory activities towards key enzymes relevant to metabolic syndrome: α-glucosidase, pancreatic lipase and angiotensin I-converting enzyme were evaluated and compared to these of reference samples: rabbit eye (REB, Vaccinium ashei J.M. Reade) and southern highbush (SHB, Vaccinium darrowii × Vaccinium corymbosum) blueberries. Polyphenolic-rich fraction obtained from DP comprised ellagic acid and ellagitannins accompanied by flavonoids: myricetin, quercetin, rutin, and anthocyanins. This fraction contained the highest level of total phenolics and exhibited superior antioxidant capacity (Ferric Reducing Antioxidant Power, FRAP and Oxygen Radical Absorbance Capacity, ORAC) to polyphenolic-rich fractions of QD, REB and SHB. DP closely followed REB and SHB in their inhibitory activities against isolated α-glucosidase (IC50 of 0.13; 0.097 and 0.091, respectively) and was the most efficient inhibitor of angiotensin converting-enzyme (ACE; 91.2% inhibition at extract concentration of 1 mg/mL). Polyphenolic-rich fraction of QD comprising hydroxycinnamic acids, quercetin and cyanidin 3-glucoside was the most effective inhibitor of pancreatic lipase (IC50: 0.60 mg/mL).

A new drying approach to enhance physical quality of konjac glucomannan extracted from Amorphophallus muelleri was studied. It consisted of a comparison between microwave vacuum drying and conventional hot-air drying. The effects of microwave vacuum drying and hot-air drying on drying kinetics and physical and structural properties such as color, bulk density, particle density, porosity, viscosity, and morphology of konjac glucomannan (KGM) flour were investigated. It can be concluded that microwave vacuum drying significantly reduced drying time and increased porosity of dehydrated products which have a positive effect on the viscosity of the KGM solution. In contrast, it decreased bulk density and particle density when compared with conventional hot-air drying. Microstructure observations revealed the presence of large cavities in the granules of microwave-vacuum-dried KGM samples. However, there was a slight change in color of the microwave-vacuum-dried samples, resulting in a lower whiteness index tha...

Fluidized bed dryers (FBDs) and spouted bed dryers (SBDs) are considered efficient dryers for drying seeds from high moisture content (MC; 20–25%wb) to medium MC (≈18%wb). In this work, a number of drying experiments and seed quality tests were conducted using rice and wheat seeds in order to compare the FBD and SBD with regard to drying rate, product quality, and specific energy consumption. It was found that FBD was better in terms of a faster drying rate and SBD was better in terms of specific energy consumption. However, it could not be clearly concluded which dryer provided a better product quality in terms of germination percentage.

Ginger and turmeric, members of the Zingiberaceae family, are widely used for their pungent and aromatic flavour in foods and also for their medicinal properties. Both crops are often grown by smallholders in mountain areas on rich former forest soils with no need for fertilizers and pesticides, fulfilling de facto the conditions of organic agriculture. They are consumed fresh or dried. Drying is often performed without taking into account the content of bioactive compounds in the dried product. Various bioactive compounds have been identified in their rhizomes, and their content affects the price of the dried product. Hence, this study focused on the effects of drying treatments and blanching on the retention of bioactive compounds in the dried products. The bioactive compounds in ginger rhizome (Zingiber officinale Roscoe) are gingerols (particularly 6-gingerol). The drying treatments that were applied to fresh ginger included constant and also changing temperature conditions. Due to the short drying time, 60 °C was the optimal drying temperature to retain 6-gingerol. However, the changing temperature conditions significantly improved the retention of 6-gingerol. As for blanching, it had a significant negative effect on 6-gingerol retention. Turmeric (Curcuma longa) is known for its bright yellow colour and pharmacological properties due to curcumin, a phenolic compound. Drying was performed under constant conditions at 38 °C, 48 °C, 57 °C and 64 °C and a relative humidity of 20% and 40%. Drying at 57 °C with a lower relative humidity was the best drying treatment, yielding the highest amount of curcumin among non-blanched samples. Blanching for 15 min exhibited the highest curcumin yield while blanching for 5 min and 30 min did not have much effect. The findings of this study will benefit the industry in terms of improved quality control and cost reduction.

Macadamia nuts are well known for their unique flavor and taste. They contain a high level of monounsaturated fatty acids such as oleic acid, which is claimed to have an effect on reducing blood cholesterol. This study focuses on monitoring the changes in the physical and chemical qualities of macadamia nuts during drying, roasting, and storage. A combination of heat pump drying and tunnel drying was selected for this study to provide a comparison with convectional hot air drying. After completion of all drying treatments, the dried nuts were subjected to roasting at 125°C for 20 min and storage in ethylene vinyl alcohol copolymer (EVOH) bags at 4°C for 3 months. After each stage of processing, nut samples were taken to assess the quality in terms of fatty acids, moisture content, water activity, peroxide value, free fatty acids, color, and volatile compounds. The experimental results showed that drying treatments using heat pump combined with tunnel drying can reduce drying time significantly. It appears...

Thin-layer drying studies were conducted on two peanut varieties, Middleton and Sutherland. The range of inlet conditions used were drying air temperatures between 35 and 55°C, air humidities of 5 to 10 g/kg, and an air velocity of 2.5 m/s. The initial product moisture contents were 39 ± 3% (Middleton) and 43 ± 4% (Sutherland). A two-compartment drying model was fitted to the experimental data. The goodness of fit was assessed by comparing correlation coefficients and sums of squares. The coefficients of determination (R 2) were greater than 0.94 for both varieties, indicating that the models were adequate to describe the drying process. The results showed that the drying air temperature was the predominant factor in peanut drying. No significant difference in drying rates was found between the two varieties.

This paper describes the effects of spray drying temperature and wall materials on functional properties of kaffir lime oil microcapsules. The effects of spray drying were studied at inlet air temperatures at 160, 180, and 200°C. Two coating materials (konjac glucomannan and gum arabic) were employed in this study. The results indicate that kaffir lime oil had antibacterial activity against all tested pathogens and was able to inhibit Vibrio cholerae comparable to a standard antibiotic. The combination of konjac glucomannan and gum arabic (KGM+GA) can enhance the yield and retention of total oil in the microcapsules more than using konjac glucomannan alone as a wall material. Increasing inlet air temperature resulted in a decrease of antibacterial activity and amount of bioactive volatile compounds. Physical and chemical properties of the microcapsules did not differ significantly (p > 0.05) in terms of process yield, a w , moisture content, efficiency in retention of total, surface and inner oil, water s...

This study was conducted in order to provide information on drying behavior of seed destined for reproduction of corn, wheat, and rice. Drying experiments were conducted in a fluidized bed dryer (FBD) with corn, rice, and wheat and in spouted bed dryer (SBD) with wheat and rice at temperatures between 40 and 80°C. The experimental data were fitted into four thin-layer drying models by a least squares method. As a result, Page's model and a two-compartment model were the best-fitted models. However, due to the limitation of these models, Page's model and the two-compartment model were modified by adding the drying temperature term. Subsequently, these models could adequately predict the drying curves under a wider range of temperatures with root mean square (RMS) of the difference between model-predicted and experimental values of less than 0.035.

Two drying treatments were applied to slices of beef: superheated steam and hot air. Drying kinetics and quality attributes such as color, water activity, and peroxide value were investigated for different drying conditions (drying medium temperature 130, 160, or 180°C; flow rate of the drying medium of 35, 45, or 55 kg/h; and sample thickness 3 mm, 6 mm, 9 mm, or minced beef). The experimental results show that superheated steam drying generally leads to shorter residence times in the dryer when the moisture content needs to be decreased below 8%. Superheated steam drying distinguishes itself by longer constant rate periods, lower critical moisture contents, and higher drying rates for the falling rate period compared to air drying. Reducing the sample thickness or increasing the transferred heat, by increasing the temperature or velocity of the drying medium, result in accelerating the drying process. Temperatures above 160°C, however, cause changes within the and its surface and prevent the bound moist...

Corn, rice, and wheat seeds with an initial moisture content (IMC) of 20–25% wb were dried to moisture content below 18% wb at 40–80°C in a fluidized bed dryer (FBD) and spouted bed dryer (SBD) and the seeds with IMC 18% wb were dried to below 14% wb at air temperatures 18–30°C and relative humidity 60–70% by an in-store dryer (ISD). As a result, it appears that a two-stage drying concept is feasible in drying high-moisture-content seeds due to the high germination rate of dried seeds. Nonetheless, the drying temperature must be carefully selected. A drying temperature of 40°C was clearly safe for all samples, whereas more than 90% of wheat seeds still germinated after drying at 60°C in FBD. Furthermore, drying seeds with IMC 18% wb by ISD was safe under specified drying conditions.

Anthocyanins were identified and quantified in various cultivars of blueberries grown in Australia. Those were Crunchie, Star and Sharpe (highbush, Vaccinium corymbosum L.) and Climax, Powderblue and Brightwell (rabbiteye, Vaccinium ashei). A method was developed involving liquid chromatography–mass spectrometry and UV–visible spectroscopy. The repeatability of injection was less than 2% relative standard deviation (RSD) while the repeatability of sample preparation was less than 10% RSD in most cases. The method was linear between 7% and 100% of the original concentration. The anthocyanin profile was similar in all cultivars but proportions of each compound were cultivar-dependent. Highbush had more early eluting peaks, i.e. more polar anthocyanins, than rabbiteye cultivars. Delphinidin, petunidin and malvidin were the major contributors to total anthocyanin content. Climax had the highest total anthocyanin content (13.7 ± 1.4 g cyanidin 3-glucoside equivalent kg−1 dry weight) and antioxidant activity (using 2,2-diphenyl-1-picrylhydrazyl as a free radical) of all tested cultivars. Rabbiteye had significantly higher total anthocyanin content than the highbush cultivars.

The effects of drying treatments including dryer type, drying conditions, and sample preparation on the composition of volatile compounds in two cultivars of dried Australian nectarines were investigated in this study. A cabinet dryer, a tunnel dryer, and a heat pump dryer were evaluated. The sample preparation included halving or slicing the fruit to different slice thickness and in different directions. The volatile compounds in fresh and dried nectarines were isolated using Likens Nickerson simultaneous distillation and extraction technique and identified by gas chromatography. The results indicated that a heat pump dryer was the best system for preservation of volatile compounds in sliced dried fruit in terms of lactones and terpenoids followed by cabinet dryer and tunnel dryer.

A mathematical model of temperature and wheat moisture content distribution inside a triangular spouted bed dryer was developed. The model is based on analysis of heat and mass transfer inside the dryer. In addition to that, an empirical bulk density model has been developed for wheat and included in the drying simulation. A laboratory-scale triangular spouted bed (TSB) dryer was used to dry wheat grain to validate the model. The dryer was divided into three sections, namely spouting, downcomer, and fountain. A series of drying runs were conducted to record moisture and temperature profile. There were two distinct regions observed during wheat drying. A constant rate period was observed during the initial drying stage and the falling rate period took place at the later drying stage. Initial moisture content and operating drying temperature governed the timing of transition from constant rate period to falling rate period. The model can be used to accurately predict the moisture content of wheat during dry...

A triangular spouted-bed dryer has been designed as part of a hexagonal continuous dryer for paddy. In the triangular-bed dryer, the spout of drying air is placed in one corner of the drying chamber. Combining six triangular units with the spout located in the center of the dryer allows a continuous process and reduces energy consumption due to the reduction of heat losses. The current study focuses on the distribution of moisture and temperature in an individual triangular bed. Models of distribution have been developed in order to provide a better understanding of the phenomena and to help in scaling-up of the design.

The purpose of this study was to develop and test a control system using supplementary heating for in-store drying of grain, to be used in major maize growing areas of Northeast China. In-store drying is using near-ambient air ventilation and the control system is aiming at maintaining the relative humidity of the drying air at a constant level. This can be achieved by increasing the temperature of the drying air by up to 5 °C using a small coal or biomass furnace. The control system is based on the results from previous studies and applies principles of the control theory. The system developed in this study includes a host PC and a distributed data acquisition and control system (DA&C). A drying simulation program, using drying equations for deep-bed drying and various quality models, has been used to investigate the effects of the control parameters and their possible interactions and to optimise the drying process. Several tests were conducted under different conditions to determine the performance of the control system in terms of response time and accuracy. Weather characteristics of key locations in Northeast China were analysed and found to be suitable for application of this control system. Pilot plant experiments and computer simulation results were compared in order to determinate control system performance. Economic aspects of the use of the control system were discussed in terms of fixed cost, labour cost and energy cost.

The thermophysical properties of the stone fruits plum, peach, and nectarine were modeled from experimental data as functions of moisture content. Samples were dried to preset moistures in a laboratory cabinet dryer, and the thermal conductivity, specific heat, apparent density, bulk density, and porosity of the fruit were determined. The thermal conductivity and specific heat were found to be linear functions of moisture content, whereas apparent bulk density and porosity followed second-order polynomials. Temperature dependence was not found to be significant.

The desorption isotherms of peach, plum, and nectarine were obtained using the gravimetric method. The experimental data were fitted with Chung-Pfost, Oswin, and GAB models using nonlinear regression. The coefficient of determination, analysis of variation, distribution of residuals, and mean relative deviation were measured to determine the validity of each model. Of the models tested, the five-parameter GAB model was found to give the best representation of the data. The isothermal data were also used to calculate the energy required for evaporation from the product surface, by means of Othmer plots, resulting in a moisture-dependent equation for the heat of desorption.

Three varieties of paddy rice, namely Langi and Amaroo from Australia and Chainart I from Thailand, were dried from high initial moisture content of about 27% down to 13–14% wet basis using a two-stage drying system. A fluidized bed dryer reduced the moisture content down to 18%. Drying experiments were carried out at 100, 125, and 150°C. Further moisture content reduction down to 14% was achieved by shade drying. As a result of these treatments, head rice yield increased proportionally with the drying temperature. In contrast to that, the yellowness, measured by colorimeter in terms of b value, showed an opposite trend. Starch characteristics were studied by Rapid Visco Analyser (RVA), x-ray diffraction, and differential scanning calorimetry (DSC). Pasting properties were affected by the drying temperature. The peak viscosity and break down were decreasing with the increase of drying temperature in all varieties while the setback values were increasing in Langi and Amaroo only. All starch sample...

The physical states of water and its freezing behaviour in shelled corn during subzero drying were determined by using 2 H NMR and 1 H MRI techniques. In this context, the 2 H NMR spin–lattice relaxation times ( T 1 ) and spin–spin relaxation times ( T 2 ) of water in corn were measured. The relaxation times were found to decrease with decreasing temperature. The results revealed that there were two main water components in corn of >30% wb (wet basis) with long and short T 1 . Both components exhibited minima around −20 °C. In more dehydrated corn (18.6% wb) only a single water component, with short T 1 and T 2 was observed. 1 H MRI images revealed the location of water and its freezing behaviour in different areas.